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Omniangles
These antennas represent a radical departure from previous attempts to design a horizontally
polarized omnidirectional antenna.
Previous attempts to create omnis have centered around shortening a half wave dipole and shaping
it into a circle or square. The intent of shortening the dipole is to “pull” more current
around towards the ends, thus creating an omni pattern. Unfortunately, the current still
diminishes substantially, resulting in an egg-shaped pattern, not the desired circular pattern
of a true omni.
The Omniangles use an electrical length that is longer than a half wave. Combining this
electrical length with the isosceles triangle shape results in a pattern that is within 0.5dB
of being a perfect omni. Additional benefits are wider bandwidth and less rain detuning than
traditional loops and slightly more gain - about 0.5dB when the full 360 degree pattern is taken
into account.
Omniangles incorporate a built in current mode balun that guarantees equal illumination of both
sides of the antenna and no radiation from the shield of the feedline. Finally, these antennas
come complete with their own stainless mounting hardware - ¾” up to 1 ½ “- nothing else to buy or
fabricate as in some other omnis.
We are often asked about the gain of the Omniangles. Because we are basically taking the
figure 8 pattern of a half wave dipole and filling in the nulls, the gain is expected to be
slightly less than the directional half wave dipole. This is the case with the Omniangles-
about –1dBd. One manufacturer adds in ground gain, raising the actual free space gain by 4 or
5dB. This is true of any horizontal antenna mounted above real ground, but we prefer to use
the standard dBd, even though it looks like less gain. Another manufacture reports +2.5dBd for
their shortened ½ wave loops; this, of course, is impossible. What it is saying is that they
actually achieve more gain than a standard dipole when the dipole is shaped into a circle,
defying the laws of electromagnetics.
Read the Omni FAQ page.




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OA-28 Not currently available
OA-50
OA-70
OA-144
OA-222
OA-432 |
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